Plastic bags



Dec. 19, 1967 v G. L. VAN HOUTTE 3,358,904

PLASTIC BAGS Filed Oct. 17, 1966 FMS/l United States Patent 3,358,904 PLASTIC BAGS Ghislain Leon Van Houtte, 4 Rue Cardinal Lavigerie, Etterbeek, Belgium Filed Oct. 17, 1966, Ser. No. 587,140 Claims priority, applicatgonllgelgium, Nov. 23, 1965,

1 Claim. (a. 229-54 ABSTRACT OF THE DISCLOSURE The present invention relates to a one piece bag of plastic material.

From the view point of the user the problem with bags of plastic material is their resistance to tearing when they are filled and particularly the resistance to tension of the holding means provided.

For solving this problem, handles have already been added, or orifices have been formed at the top of each wall to be used as handgrips or holes through which thin strings were passed have been provided. These systems have, however, various drawbacks.

It handles are provided it is necessary to manufacture two objects separately-bag and handles-which then have to be assembled, for example by welding.

If handgrips cut into the bag are provided, it is absolutely necessary that the bag be made from a material having an appropriate strength or that at least the cut portion be reinforced in order to avoid tearing under tension. The same applies to the system with thin strings which furthermore cut the hand when the load reaches a certain weight.

It has also already been proposed to cut the plastic bags from a piece of flexible tube, the upper and lower ends of which are closed by transverse welding seams, and to form on the upper edge handgrips which extend at right angles to the upper transverse welded seam. These handgrips have at their top edge welded joints, which give rise to the fear that they will tear when the load reaches a certain weight. Furthermore the connection of such handgrips with the body of the bag can also be the place where tears occur. If in order to avoid such tears the lateral portions of the bag, where the handgrips are provided, are

reinforced by folds or else if the bag is made from a relatively thick material, a great deal of material will be used.

The present invention does not have these disadvanrages. In the present invention the bag is constructed so that the bag periphery stressed by the load is continuous and seamless.

According to a preferred embodiment, the gripping means consist of two straps made from endless strips which are integral with the walls of the bag and are bounded by the cutting line in such a manner that the straps converge towards the exterior of the bag, the cutout made between the straps providing access to the interior of the bag. This arrangement of the straps allows one 3,358,904 Patented Dec. 19, 1967 to grip themvery easily and allows the straps to be extended in a more uniform fashion along the axis of tension of the bag when the latter is filled, i.e. according to this arrangement the stresses occuring in the straps are distributed more uniformly.

The invention as defined above allows one to manufacture a one piece bag from a plastic material having an exceptional resistance to tension whilst using only a plastic material of a very small thickness. Whilst in present practice a plastic bag can not be manufactured with a thickness of the plastic material of mm., the method according to the invention permits one to use, with at least equal resistance, a thickness of material of a few hundredths of a millimetre. Hence an appreciable economy of material and thus a reduction of the cost price is achieved. Furthermore, all the load of the bag is supported by a single unwelded piece, hence an increase in the strength of the bag is provided. A preferred embodiment of the invention will be described in connection with the accompanying drawings, in which:

FIGURE 1 shows a piece of tubing forming the rough shape of the bag.

FIGURE 2 shows the bag produced from the piece of FIGURE 1, after having cut out the portions C, D, E and made the straps F and F.

FIGURE 3 shows the bag of FIGURE 2, with the straps turned outwardly.

FIGURE 4 shows the bag of FIGURE 2 in the carrying position, the straps being joined and superimposed at their top.

In FIGURE 1, a piece of a flexible tube forming the rough shape of the bag, is shown. This piece is obtained by transverse cuts from a length of tubing along lines A and A. The periphery B, B, B is continuous and seamless. The side edges A and A are welded together in order to form the rough shape of the bag, this bag thus being closed on all its four sides.

FIGURE 2 shows the bag made from the piece of FIG- URE 1 after having cut out the portions C, D, E from the upper part of the bag.

It can be seen that the straps F and F are thus produced in such a way that the continuous periphery B, B, B is stressed by the load. The strength of the bag is thus substantially increased while at the same time there is no fear that the gripping portions of the bag will tear. According to the preferred embodiment shown, the straps F and F are cut obliquely and converge at their top, the stresses due to the pull of the bag when loaded being thus distributed in a more uniform manner. Furthermore, the straps are extended in a more uniform fashion along the axis of tension of the bag. It has been found advantageous to give a rounded shape to the connection of the straps to the body of the bag in order to increase the strength of the connection.

The length and width of the straps are chosen according to the dimensions of the bag and their spacing is chosen so as to readily fold outwardly, as shown in FIGURE 3, in such a manner that a complete opening for entry to the bag is not impeded.

FIGURE 4 shows the disposition of the straps for carrying by hand. The tops of the straps are superimposed in such a manner as to form in the hand a non cutting, very soft, double strap support, having a high tension strength due to the converging arrangement of the straps.

What I claim is:

A bag of weldable sheet plastic material in the form of a flattened seamless tube providing front and back panels, the panels having their side edges welded together to pro- 3 4 vide a closed bag with a seamless top and bottom and References Cited seamed side edges, an integral loop-shaped handle formed UNITED STATES PATENTS as two spaced apart integral loop straps extending obliquely toward the top center of the bag and provided by re- 1,808,375 6/1931 Ploosfer 150 1*7 moving a top central portion as Well as the top corner 5 3,180,557 4/1965 Thuhn 22954 edges of the closed bag so that the bag bottom, front and back panels, and integral loop handle which are stressed JOSEPH LECLAIR Prlmary Examiner by a load in the bag are seamless and continuous. R. PESHOCK, Assistant Examiner. 

